There is a strong need to assess the physiological development of the fetus, as more pre- and fullterm babies survive with possible disorders. This Phase I research will evaluate the feasibility of developing a new, non-invasive fetal magnetocardiography (fMCG) sensor, based on high temperature superconductors (HTS). The potential of fMCG is especially high for evaluating fetal rhythm disorders. Studies have shown that fMCG can detect fetal rhythm disturbances that cannot be detected by ultrasound, which is the only technology in wide use. fMCG is also a nearly ideal signal source for fetal heart rate monitoring, providing a precise signal, which can be detected throughout the last half of pregnancy. Studies have shown that fMCG can provide important diagnostic information, unobtainable by other means, which have the potential to improve the accuracy of fetal monitoring. This Phase I will (1) build a proof-of-principle HTS axial gradiometer fMCG system, with a gantry and sensor configuration based on prior MCG data from fetal heart signals, (2) assess the sensitivity of the fMCG system in terms of signal size, magnetic field resolution, and noise characteristics in shielded and unshielded envrionments, and begin to refine noise reduction software, and (3) collect fetal data at several intervals from gestation, from within the magnetically shielded room at the University of Wisconsin's Biomagnetism Research Laboratory. A major obstacle to acceptance of present-day fMCG is its high cost and sophistication. If successful, the proposed project will lead to the development of a practical instrument which can significantly improve clinical assessment of fetal cardiac function and fetal well-being.